USPTO Patents Application 10567929

Application No. 10/567,929

Reply to Office Action of October 20, 2008

REMARKS/ARGUMENTS

Claims 1-6, 8-13 and 15-26 are active. Claims 15, 19 and 25 are withdrawn. Claim
26 is constructively withdrawn.

The claimed invention provides a photovoltaic device having a composition of carbon
nanotubes and of at least one organic hole conductor, which is useful for generating
electricity from light. According to the claimed invention, the band gap of the carbon
nanotubes lies in the range of from about 0.5 to about 1 eV and therefore lower energy light
in comparison to conventional photovoltaic devices is absorbed and converted to electrical
energy. Therefore, the photovoltaic devices according to the claimed invention are more
efficient in terms of energy conversion, and are advantageously produced from relatively low
cost organic materials.

Applicants have described the significant improvement in conversion of lower energy

light to electricity on page 10, lines 1-10, in the specification as follows:

The present invention provides for a network of electron- and hole-
acceptors (and therefore also hole- and electron-donors) combining both a
good charge carrier transfer from the donors to the acceptors and a good
carrier mobility within the constituents of the network.

It furthermore provides for a more effective absorption of light in the
visible and near- infrared region, which distinguishes the devices
according to the present invention from the devices of the prior art, e.
g. organic solar cells based on fullerenes. The absorption spectra of the
latter are centered in the short wavelength region of the visible spectra and
therefore, without wanting to be bound by any mechanistic theory, show
minor power conversion efficiencies. (Bold added)

Since the band gap of the organic hole conductor is about 2 eV, i.e., is significantly
larger than the band gap of the carbon nanotube system, the claimed photovoltaic covers a
much wider range of photon energies. Therefore, the claimed device is better adjusted to the

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Application No. 10/567,929

Reply to Office Action of October 20, 2008

different spectra of commonly available light sources and will provide more efficient
conversion of light, independent of the irradiation source, than conventional solar devices.

The rejection of Claims 1, 3-4, 7-8, 1 1 16-17 and 23-24 under 35 U.S.C. 102(b) or in
the alternative under 35 U.S.C. 103(a) over Ago et al . ("Composites of Carbon Nanotubes and
Conjugated Polymers for Photovoltaic Devices," Advanced Materials, VCH
Verlagsgesellschaft, Weinheim, DE, vol. 1 1, no. 15, 20 October 1999 (1999-10-20), pages
1281-1285)("Composites") with support of Ago et al. ("Electronic interaction between
photoexcited poly(p-phenylene vinylene) and carbon nanotubes," Physical Review B, Vol.
61, No. 3, 15 January 2000, 2286-2290)("Electronic interaction) is respectfully traversed.

Applicants respectfully note that Ago ("Electronic interaction") is cited as a "teaching
reference," on page 4, line 14, of the above identified Official Action. However, no direct
citing of this reference is made.

The Office has stated (Official Action dated October 20, 2008, page 4, lines 16-23):

Ago et al (Composites also discloses MWNT as small-gap
semiconductors (the activation energy (i.e., band gap) is 3-14 meV .... As
ling as the band-gap of the carbon nanotube is smaller than the one of the
organic hole conductor, a photovoltaic effect will be observed. In addition,
the specification of the present application does not mention any
unexpected results for a band-gap of 0.5 eV - 1 eV.

Applicants respectfully note that the claimed invention describes a band gap of from
0.5 to 1.0 eV and Applicants have described that according to the claimed device, lower
energy light in comparison to conventional photovoltaic devices is absorbed and converted to
electrical energy. Applicants respectfully submit that such significant improvement in light
energy conversion to electrical energy sufficiently supports the patentability of the claimed
invention.

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Application No. 10/567,929

Reply to Office Action of October 20, 2008

Moreover, regarding Ago (Composites) disclosing MWNT as small-gap

semiconductors, Applicants again respectfiilly point to the description in the cited reference,

beginning at line 5 in column 2 to understand the reference description.

'The structure of the photovoltaic devices is shown in Figure 4a,
where PPV and MWNT layers have 210 and 140 nm thickness
respectively. The MWNT layer was used as the hole-collecting
electrode , because of its relatively high conductivity (8 S/cm at room
temperature) 1 131 and high work function £5J_eV) [16 l" (Bold and
underline added)

Applicants respectfully submit that nowhere does this combination of references
disclose or suggest carbon nanotubes having a band gap in the range of from about 0.5 to
about 1 eV., and nowhere does this combination of references describe the MWNT layer as
the layer intermediate between the two electrodes as according to the claimed invention.

Applicants respectfully submit that Claims 3-4, 7-8, 11, 16-17 and 23-24, all directly
or indirectly depend from Claim 1, and therefore include the patentable subject matter
described in Claim 1 .

In view of all the above, withdrawal of the rejection of Claims 1, 3-4, 7-8, 1 1 16-17
and 23-24 under 35 U.S.C. 102(b) or in the alternative under 35 U.S.C. 103(a) over Ago
(Composites) with support of Ago ("Electronic Interaction") is respectfully requested.

The rejection of Claims 2, 6, 9-10, 12-13, 18 and 21-22 under 35 U.S.C. 103(a) over
over Ago (Composites) with support of Ago ("Electronic Interaction") and further in view of
Kymakis et al . ("Single-Wall Carbon Nanotube/Conjugated Polymer Photovoltaic Devices,"
Applied Physics Letters, American Institute of Physics. New York, Us vol. 80, no. 1, 7, pages
1 12-1 14) is respectfully traversed.

Applicants respectfully note that Claims 2, 6, 9-10, 12-13, 18 and 21-22, all directly
or indirectly depend from Claim 1 . The deficiencies of the primary combination of
references relative to Claim 1 and claims dependent thereon have been described above.

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Application No. 10/567,929

Reply to Office Action of October 20, 2008

Kymakis describes a photovoltaic device containing poly(3-octylthiophene) and

single walled carbon nanotubes. Fig. 2 shows the Absorption spectra of the composite and in

discussing the spectra, states:

"The absorption spectra of the P30T show no significant change
upon adding 1% of nanotubes by weight. This implies that in the blend, no
significant ground state interaction is taking place between the two
materials, . . . From the absorption spectra of the P30T, an optical band gap
of 2.4 eV can be derived. "

Further, on page 1 14, left column, lines 16-25, Kymakis describes that the
workfimction of SWNTs ranges from 3.4 to 4 eV. Nowhere does this reference disclose or
suggest carbon nanotubes having a band gap from about 0.5 to about 1 eV., and therefore this
cited reference cannot cure the deficiencies of the cited primary references.

In view of the foregoing, Applicants respectfully submit that the cited combination of
references can neither anticipate nor render obvious the claimed invention, and withdrawal of
the rejection of Claims 2, 6, 9-10, 12-13, 18 and 21-22 under 35 U.S.C. 103(a) over Ago
(Composites) with support of Ago ("Electronic Interaction") and further in view of Kymakis
is respectfully requested.

The rejection of Claim 5 under 35 U.S.C. 103(a) over Ago (Composites) with support
of Ago ("Electronic Interaction") and further in view of Tsukamoto et al. (JP 2003-096313) is
respectfully traversed.

Tsukamoto describes a Field Effect Transitor wherein a composite of carbon
nanotubes and organic polymer is used as a semiconductor.

Applicants respectfully note that Claim 5 directly depends from Claim 1 .

Tsukamoto is cited to show carbon nanotubes being a mixture of multi-walled and
single-walled carbon nanotubes. This reference is silent with respect to a band gap for the
carbon nanotubes and as previously discussed (Response to Official Action dated April 24,
2008, filed August 25, 2008), carbon nanotubes are generally known to have band gaps of 3

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Application No. 10/567,929

Reply to Office Action of October 20, 2008

eV or higher. Accordingly, Applicants respectfully submit that this secondary reference
neither discloses nor suggests a device having carbon nanotubes with a band gap which is in
the range of from about 0.5 to about 1 eV.

In view of the above, Applicants respectfully submit that the cited secondary
reference cannot cure the deficiencies of the primary reference combination. As the cited
combination of references can neither anticipate nor render obvious the claimed invention,
withdrawal of the rejection of Claim 5 under 35 U.S.C. 103(a) over Ago (Composites) with
support of Ago ("Electronic interaction") and further in view of Tsukamoto is respectfully
requested.

The rejection of Claim 12 under 35 U.S.C. 103(a) over Ago (Composites) with
support of Ago ("Electronic interaction") and further in view of Forrest et al. (U.S.
6,451,415) is respectfully traversed.

Claim 12 directly depends from Claim 1 and the deficiencies of each of the cited
primary reference combination is described above. Forrest is cited to show a multilayer
structure. This reference describes photodetector organic photosensitive optoelectronic
devices having multilayer structures and an exciton blocking layer. However, Forrest does
not disclose or suggest multilayers containing carbon nanotubes having a band gap in the
range of from about 0.5 to about 1 eV., and therefore, cannot cure the deficiencies of the
primary reference combination. Accordingly, withdrawal of the rejection of Claim 12 under
35 U.S.C. 103(a) over Ago (Composites) with support of Ago ("Electronic interaction") and
further in view of further in view of Forrest is respectfully requested.

The rejection of Claim 20 under 35 U.S.C. 103(a) over Ago (Composites) with
support of Ago ("Electronic interaction"), further in view of Kymakis and further in view of
Ganzorig et al . (Alkali metal acetates as effective electron injection layers for organic
electroluminescent device," Materials Science and Engineering B, Elsevier Sequoia,

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Application No. 10/567,929

Reply to Office Action of October 20, 2008

Lausanne, Ch, vol. 85 no. 2-3, 22 August 2001 (2001-08-22), pages 140-143) is respectfully
traversed.

Ganzorig is cited to show the addition of an LiF, CsF or Li acetate interlayer between
the Al electrode and the organic hole conducting compound layer. Applicants respectfully
submit that nowhere does Ganzorig disclose or suggest a composite of carbon nanotubes and
of at least one organic hole conductor, wherein the band gap of the carbon nanotubes lies in
the range of from about 0.5 to about 1 eV., and therefore does not cure the basic deficiency of
the primary reference combination. Accordingly, withdrawal of the rejection of Claim 20
under 35 U.S.C. 103(a) over Ago (Composites) with support of Ago ("Electronic
interaction"), further in view of Kymakis and further in view of Ganzorig is respectfully
requested.

The constructive restriction of Claim 26 is respectfully traversed.

U.S.C. 37 C.F.R. § 1.475 (b)(3) states, in pertinent part:

An international or a national stage application containing claims to
different categories of invention will be considered to have unity of
invention if the claims are drawn only to one of the following combinations
of categories:

(3) A product, a process specially adapted for the manufacture of
said product and a use of said product; . . .

Applicants respectfully submit that the Office has not considered U.S.C. 37 C.F.R. §

1 .475 (b)(3) and therefore has failed to meet the burden necessary in order to sustain the

requirement for restriction. Applicants therefore request that the requirement for restriction

be withdrawn.

The objection to the drawings under 37 CFR 1 .83(a) is respectfully traversed.

Applicants respectfully call the Examiner's attention to 37 CFR 1.81 (b) which states:

Drawings may include illustrations which facilitate an
understanding of the invention (for example, flow sheets in cases of
processes, and diagrammatic views).

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Application No. 10/567,929

Reply to Office Action of October 20, 2008

Applicants respectfully submit that Figs. 1 and 2 facilitate an understanding of the
invention and therefore according to 37 CFR 1.81 (b), should be acceptable under 37 CFR
1 .83. Accordingly, withdrawal of the objection to the drawings under 37 CFR 1.83(a) is
respectfully requested.

Applicants respectfully submit that the above-identified application is now in
condition for allowance and early notice of such action is earnestly solicited.

Respectfully submitted,

OBLON, SPIVAK, McCLELLAND,
MAIER & NEUSTADT, P.C.

Jay ET Rowe, Jr., Ph.D.
Registration No. 58,948

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